First I've heard or read about that... maybe it's not a bug... in situations like this we normally ask the person to try Firefox in safe-mode to see if the problem still occurs...

Try running Firefox in safe-mode...NOTE: This is a testing procedure only ... NOT for normal browsing.-- On the menu bar, click the Help menu and select Restart with Add-ons Disabled....Firefox will start up with the Firefox Safe Mode dialog. Click continue in Safe Mode and don't check any items.

Note: You can also start Firefox in Safe Mode by holding down the shift key while Single/Double clicking on the icon.* (option key while starting Firefox on Mac).----------------------------------------------------------------------------------------->What safe-mode does ..... Safe Mode temporarily affects the following: * All extensions are disabled. --- * The userChrome.css and userContent.css files are ignored. * The default theme is used, without a persona. --- * The default toolbar layout is used. * The Just-in-time (JIT) JavaScript compiler is disabled. --- * Hardware acceleration is disabled.

-- Safe Mode has no effect on the following -- * The status of plugins is not affected. * Custom preferences are not affected.

The problem doesn't seem to occur in the safe mode. I opened many tabs and waited for memory usage to be high (1700 MB), but drag-and-dropping didn't cease to work.So yeah, it's got to be one of my installed add-ons.

Try disabling all extensions but one and then close and restart the program. (Disable them by using menu path Tools->Addons->Extensions->click on "Disable" for every extension but one.) See if the problem is present. If not, enable an additional extension and close and restart the application. Repeat this procedure until the problem reappears. The last enabled extension will be the cause of the problem.

counterargon wrote:The problem doesn't seem to occur in the safe mode. I opened many tabs and waited for memory usage to be high (1700 MB), but drag-and-dropping didn't cease to work.So yeah, it's got to be one of my installed add-ons.

What? ... that must have been MANY tabs... how many and what type?

As you can see she's (The CAT) always alert and on the prowl for Meoware !!